Perhaps you should try some spelling variations:
sang dai » sang tai, lang dai, sang mai
ky sang » ky nang, ky dang, ky tang
dai hoi » dai hoc, dai hai, dai moi
hieu su » hieu sau, tieu su, hieu so
su phat » su pham, tu phat, xu phat
tu sai » tu bai, tu san, tu cai
sai ky » sac ky
xac va » tac va, ac va, bac va
vi cua » vai cua, di cua
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sai ky sang dai hoi. hieu su phat ((xac va) or (duc va)) hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sai ky sang dai hoi. hieu su phat ((xac va) OR (duc va)) hanh vi cua te.
• Adding a wildcard symbol may retrieve word variants: tu sai ky sang dai hoi. hieu su phat ((xac va) or (duc va)) hanh vi cua te*.